The present invention relates to beds and, more particularly, to adjustable, multiple position care beds.
Adjustable or articulating beds are commonly used in the healthcare field. A typical bed includes a base and a mattress frame or support which is divided into a head or back section, a seat section and a leg or foot section. The mattress frame sections are pivotally interconnected and have a continuous range of adjustment. The sections are moveable from a flat, patient resting position to a seated position with the legs bent or the legs straight and the patient's back angled upwardly with respect to the seat section. The sections are pivoted by motor drives, hand operated cranks or through the patient's weight.
An example of a multi-position adjustable bed may be found in commonly owned U.S. Pat. No. 5,105,486 entitled ADJUSTABLE BED, which issued on Apr. 21, 1992 to Peterson. The bed disclosed therein includes a mattress frame having a head section, a seat or intermediate section and a foot section, which are pivotally interconnected. A first link and positioner subassembly interconnects the head section with the seat section and a second link and positioner subassembly interconnects the seat section with the foot section. Each link and positioner subassembly includes an elongated rod and a lock mechanism. The lock mechanism selectively positions the rod with respect to a lock housing and, hence, the mattress sections with respect to each other. In addition, a high/low mechanism is provided for raising the mattress frame from a low position to a high position for easier patient care. The mattress frames may be articulated with respect to each other when the frame is in the high and/or low positions.
Examples of other adjustable beds may be found in U.S. Pat. No. 3,036,314 entitled ADJUSTABLE BED, which issued on May 29, 1962 to Wetzler; U.S. Pat. No. 3,059,248 entitled ADJUSTABLE BED, which issued on Oct. 23, 1962 to Wetzler; U.S. Pat. No. 4,258,445 entitled BEDS AND ADJUSTABLE BODY SUPPORTING ASSEMBLIES, which issued on Mar. 31, 1981 to Zur and U.S. Pat. No. 4,472,846 entitled COUPLING SYSTEM FOR THE MOTOR DRIVE IN AN ADJUSTABLE MOTORIZED HOSPITAL BED, which issued on Sep. 25, 1984 to Volk, Jr. et al. The Wetzler patents disclose adjustable beds including high/low mechanisms and a single drive motor. In Volk, Jr. et al., an adjustable bed is disclosed wherein different adjustment functions including high/low, back and knee adjustments are made by a single, reversible motor which is selectively coupled to a plurality of output drive shafts by a multiple clutch arrangement.
In the vast majority of instances, the full range of adjustment available with beds heretofore provided is not used. The most common mode of operation is to raise the mattress surface or sleeping surface in a flat configuration to a high position when patient care is being given. Raising the sleeping surface reduces back strain while changing dressings, bandages, clothes and performing other like operations. When a patient is left unattended, the bed is typically placed in its lowest position in an attempt to reduce possible injury in the event the patient tries to leave the bed or falls out of the bed. When articulating the mattress sections, typically the back or head section is the most frequently used mode. The back section is raised while the bed is in the low position. Back section elevation is used to increase the comfort of the patient while eating, reading, conversing, watching television and the like. In addition, a patient will typically use the back section as an arm support while exiting the bed. As a result, exiting of the bed should be done while the bed is in the low position. The standard operating requirements or most typical operational modes of an articulating bed are, therefore, a) elevated in a flat position and b) back articulation in a low position.
A need exists for an adjustable or articulated bed of reduced complexity from that heretofore provided, which meets the most common operating modes or requirements and which may be manufactured at a reduced cost with increased reliability.